You may be able to get an edible cake using milk but it won't taste the same. If the recipe calls for baking soda, the sour cream would provide the acidic environment necessary to get the soda to work. Milk does not.

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"If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan

One thing you could do, though it won't be perfect, is to make "buttermilk" out of whole milk by putting a couple of tablespoons of vinegar in a measure and filling it with milk to the amount called for. Stir it up and let sit at room temperature about 5 - 10 minutes. I have purposely suggested a high vinegar content to bring up the acidity and hopefully thicken the milk.

Besides acidity, sour cream is thick and milk is thin. The texture of the cake will be affected if more liquid is used than necessary.

You may be able to get an edible cake using milk but it won't taste the same. If the recipe calls for baking soda, the sour cream would provide the acidic environment necessary to get the soda to work. Milk does not.

can the addition of lemon or vinegar to the
milk do almost same thing?

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__________________...Trials travel best when you're taking the transportation known as prayer...SLRC